The objective of this investigation is to increase our understanding of the role of proteins in the regulation of neuronal function through a study of the intra-axonally transported proteins. Using the retinal ganglion cells of the rabbit visual system as an experimental model, these proteins will be characterized with regard to their physical properties, transport velocities, turnover rates, intra-cellular localization, identity and, if possible, function. Attention will be focussed upon proteins showing altered transport properties associated with neuronal stimulation, visual deprivation and development, with the hope that the characterization of these proteins will contribute to an understanding at the molecular level of such processes as regulation of transmitter synthesis, specification of interneuronal connections and synaptogenesis. Intra-axonal transport will be compared in different neuronal systems and in different species to establish on the one hand the degree of university, and on the other hand the degree of uniqueness of the velocities and compositions of transported proteins. A genetically aberrant protein which has been identified in the optic nerve and tract of albino animals will be analyzed further in an effort to determine the effect of the genetic alteration upon nervous system function. BIBLIOGRAPHIC REFERENCES: Willard, Mark B. 1976 Genetically determined protein polymorphism in the rabbit nervous system. Proc. Natl. Acad. Sci. USA, 73: 3641-3645. Willard, Mark B. and Hulebak, K.L. 1977 The intra-axonal transport of polypeptide H: evidence for a fifth (very slow) group of transported polypeptides in the retinal ganglion cells of the rabbit. Brain Research, in press.